Change test video size to 1080p

Change-Id: I428f520a7018bd80cfc1cb7ac12864770168eb46

test/motion_vector_test.cc

@@ -81,7 +81,7 @@ TEST_P(MotionVectorTestLarge, OverallTest) {
 
   // Reduce the test clip's resolution while testing on 32-bit system.
   if (sizeof(void *) == 4) {
-    width = 2048;
+    width = 1920;
     height = 1080;
   }